Cap for spark plug wire retainer



FIG. 1 shows a top back left perspective view of a cap for a spark plug wire retainer showing my new design;

FIG. 2 shows a bottom back left perspective view thereof;

FIG. 3 shows a top view thereof;

FIG. 4 shows a bottom view thereof;

FIG. 5 shows a left side view thereof;

FIG. 6 shows a right side view thereof;

FIG. 7 shows a front view thereof; and,

FIG. 8 shows a back view thereof.

The broken lines shown represent portions of the cap for spark plug wire retainer that form no part of the claimed design. 

CLAIM I claim the ornamental design for a cap for a spark plug wire retainer, as shown and described. 